Certain refrigerator appliances include a dispensing system for dispensing ice and/or liquid water. Such dispensing system generally include an actuator, such as a button or paddle, for initiating a flow of ice and/or liquid water into a dispensing area of the dispensing system. By pressing the actuator, a user can initiate the flow of ice and/or liquid water into a receptacle, such as a cup or pitcher, positioned within the dispensing area.
Certain dispensing systems can include one or more sensors for performing automatic filling of the receptacle, such that the user is not required to operate an actuator. For example, such dispensing systems can employ vision-based sensing (e.g. a camera an associated image processing software), ultrasonic sensors, or magnetic sensors. However, each of these types of sensors suffers from various drawbacks.
As an example, vision-based sensing requires relatively expensive components such as a camera and hardware and software for performing image processing. In addition, under certain usage conditions, vision sensors can become contaminated with foreign material including, but not limited to, colas, juices, food particles, or other contaminants or pollutants. For example, such contaminants can become affixed to or otherwise impair or inhibit proper operation of the vision sensor by clouding or otherwise blocking the imagery captured by the vision sensor.
Ultrasonic sensors can have difficulty accurately and precisely measuring various parameters such as water level, container heights, or other parameters. As an example, ultrasonic sensors can also become contaminated with foreign material. Operation of the ultrasonic sensor assembly while in a contaminated state (i.e. with substantial contaminants present) can result in decreased performance. For example, a contaminated ultrasonic sensor assembly may exhibit increased detection of false positives, failure to detect an object at all, or other improper operations. Likewise, magnet-based sensors tend to be unreliable and can result in poor system performance.
Therefore, improved systems and methods for receptacle auto fill are needed. In particular, systems and methods for receptacle auto fill that are relatively inexpensive, reliable, and insensitive to environmental contaminants and conditions are desirable.